mcs/class/referencesource/System.Activities.Presentation/System.Activities.Presentation/System/Activities/Presentation/Model/FakeModelItemImpl.cs

   1 //-----------------------------------------------------------------------------
   2 // Copyright (c) Microsoft Corporation.  All rights reserved.
   3 //-----------------------------------------------------------------------------
   4
   5 namespace System.Activities.Presentation.Model
   6 {
   7
   8     /// <summary>
   9     /// FakeModelItemImpl - purpose of this class is to allow full model editing expirience, without need to participate within model tree operations
  10     /// If you use this class, even though it contains reference to ModelTreeManager, you are not affecting actual model tree. Any changes made to the
  11     /// model, do not result in any undo/redo operations
  12     /// see aslo DesignObjectWrapper class for more usage details
  13     /// </summary>
  14     sealed class FakeModelItemImpl : ModelItemImpl
  15     {
  16         public FakeModelItemImpl(ModelTreeManager modelTreeManager, Type itemType, object instance, FakeModelItemImpl parent)
  17             : base(modelTreeManager, itemType, instance, parent)
  18         {
  19         }
  20
  21         public override ModelItem Root
  22         {
  23             get
  24             {
  25                 if (this.Parent == null)
  26                 {
  27                     return this;
  28                 }
  29                 else
  30                 {
  31                     return this.Parent.Root;
  32                 }
  33             }
  34         }
  35
  36         protected override void OnPropertyChanged(string propertyName)
  37         {
  38             IModelTreeItem modelTreeItem = (IModelTreeItem)this;
  39             ModelItem currentValue;
  40             //if property value has changed - remove existing value, so the ModelPropertyImplementation will
  41             //force reading the value from the underlying object
  42             if (modelTreeItem.ModelPropertyStore.TryGetValue(propertyName, out currentValue))
  43             {
  44                 IModelTreeItem valueAsTreeItem = (IModelTreeItem)currentValue;
  45                 //cleanup references
  46                 valueAsTreeItem.RemoveParent(this);
  47                 valueAsTreeItem.RemoveSource(this.Properties[propertyName]);
  48                 //remove from store
  49                 modelTreeItem.ModelPropertyStore.Remove(propertyName);
  50             }
  51             base.OnPropertyChanged(propertyName);
  52         }
  53     }
  54 }